Is there a relation between the hemodynamic effects of right and left ventricular pacing and the optimal v-v interval in biventricular pacing?

Abstract

Aim To investigate the relationship of right and left ventricular pacing and the optimal interventricular pacing interval (V-V interval) in biventricular (BiV) pacing in patients with chronic atrial fibrillation (AF). Methods 31 patients (21male, age 67±18.3 years) with heart failure class III - IV, left ventricular (LV) asynchrony and right ventricular (RV) pacing as baseline rhythm had BiV systems implanted. All patients were in chronic AF. Ventricular leads were positioned in the apex or mid septum of the RV, and in one of the postero-lateral branches of the coronary venous system for LV pacing.The hemodynamic effect of pacing was evaluated by invasive measurement of left ventricular (LV) dP/dtmax, performed by a pressure sensor tipped 0.014″ guide wire positioned in the LV cavity. LV dP/dtmax was measured during RV, LV and BiV pacing and BiV pacing with optimization of the V-V interval (BiVopt). Correlation between the logarithm of the ratio between RV and LV pacing and the optimal V-V interval was evaluated by Pearson correlation and Kendall's tau correlation statistics. Results The Pearson correlation between the logarithmic LV versus RV maximum dP/dt ratio and the optimal V-V interval is 0.55 (p=0.0013). There is also a strong relationship between the superiority of LV pacing over RV pacing and the optimal V-V interval being positive (Kendall's tau = 0.68, p=0.0002) Conclusion In patients with chronic AF there is a clinical significant correlation between the ratio of LV dP/dtmax during LV and RV pacing and the optimal V-V interval. Further study is necessary to determine whether this relationship can be used for optimizing the V-V interval in BiV pacing by measuring the effect of RV and LV pacing separately.